The present invention relates generally to broadband and wireless communications and more particularly to a dynamic resource partitioning for long-term fairness to non-elastic traffic on a cellular basestation.
Resource partitioning is an important problem in cellular networks, especially with the emerging focus on non-elastic traffic, such as video, and the greater requirement for quality of user experience. Resource partitioning can be done with admission control for either voice traffic or for elastic data traffic such as Web surfing; this is because the bandwidth requirement of voice traffic is predictable, whereas elastic data traffic benefits incrementally from whatever bandwidth is available. However, with non-elastic traffic such as video, resource partitioning has to trade-off well between the number of users selected for service at any instant of time and the perceived quality of service.
For best performance, non-elastic application flows such as those carrying video traffic should ideally be “guaranteed” a minimum reservation of bandwidth. Further, only enough number of flows should be admitted such that their reservations can be satisfied. However, statically reserving bandwidth to meet every flow's requirements wastes precious wireless resources when there is not enough traffic for the flows that reserved bandwidth. Admitting more flows can improve utilization, but at the cost of violating the minimum reservations of bandwidth when all flows have packets to transmit. Violating the minimum reservations can have adverse effects on the quality of experience perceived by users.
In the past, resource partitioning was done using admission control, which has been done by determining at the arrival time of a new user, whether a minimum bandwidth requirement of the new user can be met, and/or when admitting the new user does not adversely affect the quality of service QoS of the existing users. If not, the user is rejected. This approach, however, leads to long-term unfairness, since some users may get rejected greater number of times than others.
On the other hand, some other proposals include admitting greater number of video flows, and dropping lower priority packets during overload. While this approach works when packets are marked as higher and lower priority, it cannot handle flows where packets are not marked or are encrypted, or where packet dropping can be detrimental. The latter is more a common case scenario.
Accordingly, there is a need for better resource management across non-elastic flows in traffic on a cellular basestation.